A freshwater biomedical core center is proposed which will synergize with the research activities of competent investigators at the Medical College of Wisconsin and the University of Wisconsin. The core center will service investigators involved in biomedical-environmental research and coordinate and foster interdisciplinary research related to the interaction of environmental chemicals with biological systems. The core center will provide animals, space, supplies and technical support for biomedical scientists with ongoing research programs who have the desire to pursue studies related to the use of aquatic species as models in disease processes or to the understanding of the mechanism of toxic interactions of chemicals in aquatic species.